.box{
  padding:10px;
  border:1px solid gray;
  display:inline-block;
  margin-right:10px;
  margin-bottom: 10px;
  cursor: pointer;
}

.left ,.right{
  float: left;
  height:600px;
}

.left{
  width:30%;
  background: gray;
}

.right{
  width:68%;
}

.active{
  background:pink;
}

.block{
  display:block;
}

.hidden{
  display:none;
}

.mask{
  width:100%;
  height:100vh;
  background: rgba(0,0,0,0.7);
  position: absolute;
  top:0;
  left:0;
  
}

.modal{
  width:400px;
  height:300px;
  border:1px solid gray;
  background: powderblue;
  position: absolute;
  top:200px;
  left:200px;
}